Estimating Ambient Air Temperature and Diagnosing Sensor Failure Using Intercooler Efficiency

ABSTRACT

Examples of the present disclosure describe systems and methods for determining an estimated ambient air temperature in an environment in which a vehicle is operating. The estimated ambient air temperature may be compared to an ambient temperature sensor value. The comparison may be used to determine whether an ambient air temperature sensor of the vehicle is functioning properly or if an error notification or fault code should be triggered.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.16/996,439 filed Aug. 18, 2020, the disclosure of which is herebyincorporated by reference in its entirety.

BACKGROUND

An engine control system of a vehicle typically controls variousdiagnostics for the vehicle. In some examples, these diagnostics aresensitive to fluctuations in air temperature. Thus, it is necessary forthe engine control system to be able to accurately determine thetemperature of air and a source of the air that is being pulled into itsair induction system.

SUMMARY

Examples of the present disclosure describe systems and methods fordetermining an estimated ambient air temperature for an environment inwhich a vehicle is operating. The estimated ambient air temperature maybe compared to an ambient temperature sensor value. The comparison maybe used to determine whether an ambient air temperature sensor of thevehicle is functioning properly or if an error notification or faultcode should be triggered. Determining the estimated ambient airtemperature and comparing it with the ambient temperature sensor valuereduces false fails when an air diverter valve associated with a vehiclechanges state due to blockage or potential blockage of an air intakemechanism of an air induction system of a vehicle.

Accordingly, the present application describes a system including aprocessor and a memory communicatively coupled to the processor. Thememory stores instructions that, when executed by the processor, performoperations. These operations include receiving an ambient airtemperature reading from an ambient air temperature sensor associatedwith a vehicle. A cooling capacity of an intercooler associated with thevehicle is determined. An ambient air flow rate of the intercoolerassociated with the vehicle is also determined. Additionally, a coolingflow rate of the intercooler associated with the vehicle is determined.An estimated ambient air temperature is then determined based, at leastin part, on the cooling capacity of the intercooler, the ambient airflow rate of the intercooler and the cooling flow rate of theintercooler. The system may then determine a difference between theambient air temperature reading and the estimated ambient airtemperature. The system triggers an error notification for the vehiclewhen the determined difference between the ambient air temperaturereading and the estimated ambient air temperature is above a threshold.

The present application also describes a method comprising receiving anambient air temperature reading from an ambient air temperature sensorassociated with a vehicle. An estimated ambient air temperature isdetermined. The estimated ambient air temperature is based, at least inpart, on a determined cooling capacity of an intercooler associated withthe vehicle, a determined ambient air flow rate of the intercooler, anda determined cooling flow rate of the intercooler. A difference betweenthe ambient air temperature reading and the estimated ambient airtemperature is determined. An error notification for the vehicle istriggered when the determined difference between the ambient airtemperature reading and the estimated ambient air temperature is above athreshold.

Also described is a method that includes determining whether a set ofvehicle operating conditions are satisfied. When the set of vehicleoperating conditions are satisfied, an ambient air temperature readingis received from an ambient air temperature sensor associated with avehicle. An estimated ambient air temperature is determined based, atleast in part, on a determined cooling capacity of an intercoolerassociated with the vehicle, a determined ambient air flow rate of theintercooler, and a determined cooling flow rate of the intercooler. Adifference between the ambient air temperature reading and the estimatedambient air temperature is determined. An error notification for thevehicle is triggered when the determined difference between the ambientair temperature reading and the estimated ambient air temperature isabove a threshold.

This Summary is provided to introduce a selection of concepts in asimplified form that are further described below in the DetailedDescription. This Summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used to limit the scope of the claimed subject matter. Additionalaspects, features, and/or advantages of examples will be set forth inpart in the description which follows and, in part, will be apparentfrom the description, or may be learned by practice of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting and non-exhaustive examples are described with reference tothe following figures.

FIG. 1 illustrates an air induction system for a vehicle according to anexample.

FIG. 2A illustrates an air induction system for a vehicle in which anair diverter valve is in an inactive state according to an example.

FIG. 2B illustrates the air induction system of FIG. 2A in which the airdiverter valve is in an active state according to an example.

FIG. 3 illustrates an example vehicle control system associated with avehicle according to an example.

FIG. 4 illustrates a set of vehicle operating conditions that may beconsidered prior to determining an estimated ambient air temperatureaccording to an example.

FIG. 5 illustrates a method for determining whether to trigger an errornotification for a vehicle based on a comparison between an ambient airtemperature reading and an estimated ambient air temperature accordingto an example.

FIG. 6 illustrates a method for determining a state of an air divertervalve of a vehicle according to an example.

FIG. 7 illustrates an example truth table that may be used to determinea state of an air diverter valve of a vehicle according to an example.

FIG. 8 is a system diagram illustrating example physical components of acomputing device according to an example.

DETAILED DESCRIPTION

Various aspects of the disclosure are described more fully below withreference to the accompanying drawings, which form a part hereof, andwhich show specific example aspects. However, different aspects of thedisclosure may be implemented in many different forms and should not beconstrued as limited to the aspects set forth herein; rather, theseaspects are provided so that this disclosure will be thorough andcomplete, and will fully convey the scope of the aspects to thoseskilled in the art. Aspects may be practiced as methods, systems ordevices. Accordingly, aspects may take the form of a hardwareimplementation, an entirely software implementation or an implementationcombining software and hardware aspects. The following detaileddescription is, therefore, not to be taken in a limiting sense.

An air induction system of a vehicle supplies air to an engine of thevehicle. In some applications, the air induction system includes an airdiverter valve that enables the air induction system to intake air fromoutside of an engine compartment of the vehicle or to intake air fromwithin the engine compartment of the vehicle. Causing the air inductionsystem to intake air from within the engine compartment typically occurswhen an air intake mechanism (e.g., a mechanism that pulls in outsideair) of the air induction system becomes blocked. For example, in snowplow, oilfield, or firefighting applications, the air intake mechanismmay become blocked by snow, dirt, embers or other particles. As such, anair diverter valve may be used to cause the air induction system to pullin air from within the engine compartment rather than from outside thevehicle.

However, a temperature of the air taken from outside of the enginecompartment is typically cooler when compared with the temperature ofthe air taken from within the engine compartment. Warmer intake air fromwithin the engine compartment of the vehicle can disrupt air temperaturemodels of the vehicle and cause false on-board diagnostic failures —especially when a control system of the vehicle cannot determine a stateof the air diverter valve.

For example, a vehicle may have an ambient air temperature sensormounted or otherwise positioned outside of the engine compartment (e.g.,on a side mirror). The ambient air temperature value may be comparedwith a second air temperature value estimated from readings by a secondair temperature sensor within the engine compartment to ensure theambient air temperature sensor is working correctly. If the ambient airtemperature value is the same (or within a threshold difference from)the second air temperature value taken by the second air temperaturesensor within the engine compartment, then the vehicle control systemdetermines that the ambient air temperature sensor is working correctly(under normal conditions).

However, if the air diverter valve causes the air induction system topull in warmer air from within the engine compartment, the second airtemperature value taken from within the engine compartment may be muchhigher than the reading taken by the ambient air temperature sensor. Ifthe control system of the vehicle does not know or cannot determine astate of the air diverter valve, the control system may not know whetherthe air induction system is pulling in cooler outside air or warmer airfrom within the engine compartment. Thus, as the ambient air temperaturevalue is compared with second air temperature value, the control systemof the vehicle may erroneously trigger a failure notification based onthe difference between the two air temperature values. In some examples,the failure notification may be associated with the ambient airtemperature sensor.

Although a specific example is given, the present application is notlimited to this particular application. The determination of a state ofthe air diverter valve can be used to reduce or eliminate a variety offalse failure notifications. For example, various temperature models ofthe vehicle may be sensitive to changes in air temperature. Thus, if astate of the air diverter valve is known, thresholds associated withthose temperature models may be adjusted accordingly. In other aspects,one or more of the temperature models may be deactivated/activated basedon a determined state of the air diverter valve.

Accordingly, the present application describes systems and methods forreducing or eliminating false failure notifications caused by use of adiverter valve of the air induction system of a vehicle. In someexamples, this is accomplished by determining an estimated ambient airtemperature using a determined efficiency of an intercooler associatedwith the vehicle. Once the estimated ambient air temperature isdetermined, the estimated ambient air temperature is compared with theambient air temperature sensor value provided by the ambient airtemperature sensor. If the difference between the estimated ambient airtemperature and the ambient air temperature sensor value exceeds athreshold for a determined amount of time or for a specified time period(e.g., a certain number of engine cycles), a fault code or other sucherror notification can be triggered.

The present application also describes a process for determining a stateor position of an air diverter valve of the air induction system of thevehicle. The position of the air diverter valve may be determined based,at least in part, on comparisons of the intercooler-based estimate ofambient air temperature, the ambient air temperature sensor value, andthe second air temperature value provided by the second sensor.Determining the position or state of the air diverter valve may also beused to better determine whether certain diagnostics of the vehicle areaccurate, whether certain diagnostics of the vehicle should be active,and/or whether thresholds associated with the certain diagnostics shouldbe adjusted.

For example, if the air diverter valve is in an active state in whichrelatively warmer air is being pulled from an engine compartment of thevehicle into the air induction system of the vehicle, certain diagnosticcapabilities of the vehicle may be deactivated (or thresholds changed).Likewise, if the air diverter valve is in an inactive state in whichcooler (when compared to the temperature of the air within an enginecompartment of the vehicle) outside air is pulled into the air inductionsystem, certain diagnostic capabilities of the vehicle may be active.

Accordingly, the present application provides a number of technicalbenefits including but not limited to: reducing air intake temperaturesensitivity for various temperature models of a vehicle engine system,thereby reducing false fails; reducing false fails by usingcomplementary fault detection techniques in parallel (or substantiallyin parallel); and enabling more robust detection of an air divertervalve by using two different air temperature models having different airtemperature sensitivities. In addition to the above, the techniquesprovided herein do not require any additional hardware, sensors, orwiring. Thus, current vehicles may be effectively retrofit with thesolutions described herein.

FIG. 1 illustrates an air induction system 100 for a vehicle accordingto an example. The air induction system shown in FIG. 1 may be used toestimate an ambient air temperature of ambient air surrounding thevehicle rather than relying solely on an ambient air temperature sensorvalue 115 provided by an ambient air temperature sensor 110 of thevehicle or a pre-compressor sensor 125 providing a pre-compressor sensorvalue. The estimated ambient air temperature may be determined based, atleast in part, on a determined efficiency or heat rejection capabilityof an intercooler 155 of the air induction system 100.

As briefly discussed above, dust, snow, embers or other particles mayblock or otherwise inhibit an air intake mechanism of the air inductionsystem 100 from pulling air from outside of an engine compartment(represented in FIG. 1 as the vertical dashed line) of the vehicle. Whenthe air intake mechanism is blocked (or may likely become blocked), anair diverter valve may switch (or be caused by an operator to switch)states and cause the air induction system 100 to pull warmer air frominside the engine compartment. However, as comparisons are made betweenair temperature readings taken from the ambient air temperature sensor110 and a pre-compressor sensor 125, the difference in temperature maycause the control system 175 of the vehicle to trigger a faultnotification. The fault notification may be in the form of illuminationof a check engine light or other such malfunction indicator lamp.Alternatively, a specific message regarding a fault related to theambient air temperature sensor 110 may be displayed to a vehicleoperator. In this example, the notification may actually be a false failbecause the ambient air temperature sensor 110 may be working correctlybut the vehicle control system 175 may be unaware that the state of theair diverter valve has changed, which is why the difference betweenreadings of the ambient air temperature sensor 110 and pre-compressorsensor 125 has increased beyond a threshold level.

In order to remedy the above, heat rejection capabilities of theintercooler 155 of the vehicle may be determined and used to determinean estimated ambient air temperature. The estimated ambient airtemperature can be compared to the ambient air temperature sensor value115 to determine an ambient air temperature error. The ambient airtemperature error may subsequently be used to determine whether an errorcondition or notification associated with the ambient air temperaturesensor 110 should be triggered. As such, a determination of the ambientair temperature error may be used to reduce or eliminate false failnotifications caused by inaccurate readings provided by the ambient airtemperature sensor 110 when the ambient air temperature sensor 110 isblocked or otherwise obstructed.

The heat rejection capability of the intercooler 155 may be determinedin real time or substantially real time. For example, the heat rejectioncapability of the intercooler 155 (also referred to as an efficiency ofthe intercooler 155) may be determined continuously or substantiallycontinuously when the engine of the vehicle is running. In otherexamples, the heat rejection capability of the intercooler 155 may bedetermined simultaneously or substantially simultaneously to the ambientair temperature sensor 110 providing ambient air temperature sensorvalues 115. In yet another example, the heat rejection capability of theintercooler 155 may be determined when a set of vehicle operatingconditions 400 (FIG. 4 ) are satisfied. The heat rejection capability ofthe intercooler 155 may also be determined periodically, in response toreceived input, at manufacturing time, in response to the engine of thevehicle starting and so on.

In FIG. 1 , ambient air 105 (e.g., air outside of an engine compartmentof the vehicle), and the subsequent intake and flow of the ambient air105 into and within the air induction system 100 and ultimately to theengine 170 of the vehicle, is represented by the solid lines anddirectional arrows. As the air 105 enters and travels through the airinduction system 100 of the vehicle, various sensors (represented byblack circles) are used to determine temperature and/or pressure values.These values may be provided to a vehicle control system 175 of thevehicle (as represented by dashed lines and direction arrows).

For example and as shown in FIG. 1 , an ambient air temperature sensor110 measures a temperature of the ambient air 105 to generate an ambientair temperature sensor value 115 (also referred to herein as T ambientsensor). The air 105 may enter an air filter 120 and a pre-compressorsensor 125 may take one or more second sensor reading(s). In someexamples, the pre-compressor sensor 125 may be a temperature sensor. Inanother example, the pre-compressor sensor 125 may be a pressure sensor.In other examples, pre-compressor sensor 125 may comprise both atemperature sensor and a pressure sensor. It is also contemplated that adetermined temperature of the air taken by the pre-compressor sensor 125may be used to determine a pressure of the air 105, and a determinedpressure of the air 105 may be used to determine a temperature of theair. Regardless of whether the pre-compressor sensor 125 is atemperature sensor and/or a pressure sensor, the output of thepre-compressor sensor 125 (pressure and/or temperature) is representedas a pre-compressor sensor value 130 (also referred to herein asp_(ambient) for a pressure reading and/or T_(pre-compressor) for atemperature reading). In some examples, a value for p_(ambient) may bedetermined from a T_(pre-compressor) reading. Likewise, a value forT_(pre-compressor) may be determined from a 10 ambient value. The air105 may subsequently enter a compressor 140.

The process for determining the heat rejection capability of theintercooler 155 will now be described. In some examples, the heatrejection capability of the intercooler 155 may change over time and/orbased on environmental conditions in which the vehicle is operating. Forexample, the heat rejection capability of the intercooler 155 may changebased on a determined or detected altitude in which the vehicle isoperating, current weather conditions, age of the vehicle, age of theintercooler 155, and so on. However, the calculations described belowmay provide current heat rejection capabilities of the intercooler 155regardless of the various factors and environmental conditions describedabove.

In the present disclosure, determining the heat rejection capability ofthe intercooler 155 is described or referred to as an intercoolerefficiency model. The intercooler efficiency model is based on atemperature drop of the air 105 as a fan of the intercooler 155 forcesthe air 105 through the intercooler 155.

In addition, the efficiency of the intercooler 155 may be based on anumber of different factors. These factors may include the ambient airtemperature of the air 105, a speed of the air 105 as it passes throughthe intercooler 155, and a current or detected speed of the vehicle. Aswill be explained in more detail below, each of these factors isconsidered by the intercooler efficiency model. The intercoolerefficiency model may be implemented by the processing and storagecapabilities of the vehicle control system 175 and/or by other computingelements associated with the vehicle.

In some examples, and as used herein, a model (e.g., the intercoolerefficiency model and/or the pre-compressor model described in moredetail below), may be a combination of hardware, software, and/or datastored in one or more data tables or another storage device. The modelsmay analyze stored data and/or received data (e.g., from varioussensors) to determine an output. The output may be subsequently used toaccomplish a determined objective. For example, the determined objectivein the present example would be a determination as to whether an ambientair temperature sensor is faulty and/ow whether an error notificationshould be triggered.

The intercooler efficiency model determines the cooling capacity of theintercooler 155 (referred to herein as “Cooling Capacity”). The CoolingCapacity of the intercooler 155 may be determined using the followingequation:

${{Cooling}{Capacity}} = {\frac{{Air\_ Mass}{\_ Flow}}{1000g/{kg}} \times {CP} \times \frac{T_{IC\_ in} - T_{IC\_ out}}{T_{IC\_ in} - T_{ambient\_ est}}}$

In the equation set forth above, Air_Mass_Flow is defined as the rate offresh air flow through the air induction system 100; CP is the specificheat of air; T_(IC_in) in is an intercooler inlet air temperature 150value provided by an intercooler inlet air temperature sensor 145associated with the intercooler 155; T_(IC_out) is an intercooler outletair temperature 165 value provided by an intercooler outlet airtemperature sensor 160 associated with the intercooler 155; andT_(ambient_est) is an estimated value for the ambient air temperature.

In some examples, an arbitrary value may initially be used forT_(ambient_est). However, once the intercooler efficiency model hasdetermined a value for T_(ambient_est), that value may be substitutedfor the arbitrary value. Thus, each time (after the initial time) theCooling Capacity of the intercooler 155 is determined, the previouslydetermined T_(ambient_est) is plugged into the equation above todetermine the current or instantaneous Cooling Capacity of theintercooler 155.

Once the Cooling Capacity of the intercooler 155 has been determined,the intercooler efficiency model accesses a data table, a lookup table,a tunable map or other such storage device that stores information aboutan ambient flow of the intercooler 155. As used herein, the ambient flow(referred to as “Ambient Flow”) of the intercooler 155 describes theability of the intercooler 155 to cool air (e.g., how efficiently theintercooler 155 cools air 105 based on the rate of fresh air flowthrough the air induction system 100). In some examples, the determinedAmbient Flow is corrected/adjusted based on a detected or determinedambient density of the air 105.

A determination of the Ambient Flow is based, at least in part, on thedetermined Air_Mass_Flow (described above) and the previously determinedCooling Capacity of the intercooler 155. For example, values associatedwith the Air_Mass_Flow and the Cooling Capacity of the intercooler 155may be input into X and Y axes of the lookup table to determine theresultant Ambient Flow. In some examples, the standard density of air isdivided out from the Ambient Flow values provided in the table.

The intercooler efficiency model may also determine the cooling flow ofthe intercooler 155. The cooling flow (referred to as “Cooling Flow”)describes the density ratio correction factor for additional heatremoval by external air flow. In order to determine the Cooling Flow ofthe intercooler 155, the intercooler efficiency model may access anotherdata table, a lookup table, a tunable map or other such storage devicethat stores information about the Cooling Flow of the intercooler 155.

As used herein, the Cooling Flow of the intercooler 155 describes theability of the intercooler to cool air. However, unlike Ambient Flow,the Cooling Flow does not account for the ambient density of air 105. Insome examples, the Cooling Flow is a function of the fan speed of theintercooler 155 and the speed of the vehicle. Thus, when the fan speedof the intercooler 155 and the speed of the vehicle are determined,these values may be provided to X and Y axes of the lookup table todetermine the resultant the Cooling Flow of the intercooler 155.

In some examples, the values for the Ambient Flow lookup table and/orthe values for the Cooling Flow lookup table are calibrated values.Thus, when various values for Air_Mass_Flow, Cooling Capacity, fan speedand vehicle speed are determined, these values may be used to accessvalues for the Ambient Flow and Cooling Flow respectively.

The intercooler efficiency model may then determine the estimatedambient temperature (T_(ambient_est)) of the air 105 based on the heatrejected by the intercooler 155. The estimated ambient temperature(T_(ambient_est)) is based on the pressure determined from thepre-compressor sensor value 130 (p_(ambient)) provided by thepre-compressor sensor 125, the determined Cooling Flow, and thedetermined Ambient Flow. The following equation may be used by theintercooler efficiency model to determine the estimated ambienttemperature (T_(ambient_est)):

$T_{ambient\_ est} = \frac{\frac{1000P_{a}}{{kP}_{a}} \times p_{ambient} \times {Cooling}{Flow}}{R_{spec} \times p_{0} \times {Ambient}{Flow}}$

where R_(spec) is the specific gas constant of air and P₀ is thestandard density of air.

Once the estimated ambient air temperature (T_(ambient_est)) isdetermined, the intercooler efficiency model determines the ambient airtemperature error (T_(erro)r) between the estimated ambient airtemperature (T_(ambient_est)) and the ambient air temperature sensorvalue 115 (T_(ambient_sensor)) provided by the ambient air temperaturesensor 110. The ambient air temperature error (T_(error)) may bedetermined by the following equation:

T _(error) =|T _(ambient_sensor) −T _(ambient_est|)

Once the ambient air temperature error (T_(error)) is determined, theambient air temperature error (T_(error)) is compared to a temperaturedifference threshold. In some examples, the temperature differencethreshold is fourteen degrees Celsius although other values may be used.

If the ambient temperature error (T_(error)) is above the ambienttemperature difference threshold for a predetermined amount of time, thevehicle control system 175 causes an error notification to be triggered.In some examples, the error notification is triggered if the ambienttemperature error (T_(error)) is above the threshold for a predeterminedamount of time (e.g., two-hundred seconds) and/or a predetermined numberof engine cycles. Triggering of the error notification may cause a checkengine light or malfunction indicator light of the vehicle to beilluminated. The check engine light may indicate that the ambient airtemperature sensor 110 is faulty.

In some examples, the ambient air temperature error (T_(error)) is onlydetermined when the vehicle control system 175 determines or verifiesthat a set of operating conditions associated with the vehicle have beenmet. That is, a set of operating conditions must be satisfied prior tothe ambient air temperature sensor value 115 being determined, theAmbient Flow being determined, the Cooling Flow being determined, theestimated ambient air temperature (T_(ambient_est)) being determinedand/or the ambient air temperature error (T_(error)) being determined.These operating conditions are shown in FIG. 4 .

For example and turning to FIG. 4 , the intercooler efficiency model mayonly calculate the ambient air temperature error (T_(error)) when thevehicle exhibits some or all of the following operating conditions: 1)the engine speed of the vehicle is in a steady state (e.g., an absolutevalue of a speed of the engine of the vehicle exceeds an engine speedthreshold for over a predetermined amount of time); 2) the speed of thevehicle is in a steady state (e.g., an absolute value of a speed of thevehicle exceeds a vehicle speed threshold for over a predeterminedamount of time); 3) a fan speed of the vehicle is in a steady state(e.g., an absolute value a speed of a cooling fan of the vehicle exceedsa cooling fan speed threshold for over a predetermined amount of time);4) a crank power of a crankshaft of the vehicle is in a steady state(e.g., an output power of a crankshaft of the vehicle exceeds an outputpower threshold for over a predetermined amount of time); 5) adetermined crank power of a crankshaft of the vehicle is greater than orequal to a crank power threshold; 6) a determined ambient flow rate ofthe intercooler is greater than or equal to an ambient flow threshold;7) a determined coolant temperature of the vehicle is greater than orequal to a coolant temperature threshold; 8) a determined run time ofthe engine of the vehicle exceeds an engine run time threshold; 9) anestimator run time is greater than or equal to an estimator run timethreshold (e.g., the intercooler efficiency model has been executingover a threshold number of times to generate an accurate estimate); 10)a determined ambient air pressure exceeds an ambient air pressurethreshold; and 11) a determination that the engine of the vehicle is notidling.

In some examples, all of the vehicle operating conditions 400 must bemet prior to the intercooler efficiency model determining one, some orall of the values described above. In other examples, a subset of thevehicle operating conditions 400 must be met prior to the intercoolerefficiency model determining one, some or all of the values describedabove.

The determination of the vehicle operating conditions 400 may beperformed while one or more of the values described above aredetermined. Additionally, the determination of the vehicle operatingconditions 400 and/or the determination of one or more of the valuesneeded for the estimated ambient air temperature (T ambient_est)determination may be performed substantially simultaneously with thedetermination as to whether the ambient air temperature error(T_(error)) is above the ambient air temperature difference thresholdfor a predetermined amount of time. Thus, the vehicle control system 175of the present disclosure may perform multiple different types ofanalysis simultaneously or substantially simultaneously.

The present application also describes how to determine a position orstate of an air diverter valve of an air induction system associatedwith a vehicle. Since the temperature of intake air impacts the accuracyof engine air manager control algorithms, it is useful that the vehiclecontrol system 175 is able to determine whether the air diverter valveis in an active state, in which the intake air is pulled from an enginecompartment of the vehicle, or whether the air diverter valve is in aninactive or normal state, in which the intake air is pulled from outsideof the engine compartment of the vehicle.

FIG. 2A illustrates an air induction system 200 for a vehicle in whichan air diverter valve 225 is in an inactive state according to anexample. FIG. 2B illustrates the air induction system 200 of FIG. 2A inwhich the air diverter valve 225 is in an active state according to anexample. As shown in FIG. 2A, when the air diverter valve 225 is in theinactive state, outside air 205 is pulled into the air induction system200 and subsequently provided to an engine 275. As shown in FIG. 2B,when the air diverter valve 225 is in the active state, generally warmerunderhood air 210 is pulled into the air induction system 200 andsubsequently provided to the engine 275.

The air induction system 200 may use information provided from twodifferent models to determine a state of the air diverter valve 225. Thefirst model is referred to herein as a “pre-compressor model.” Thesecond model is referred to as the “intercooler efficiency model.” Theintercooler efficiency model is similar to the intercooler efficiencymodel described above with respect to FIG. 1 .

In both models, an ambient air temperature sensor 215 is used to measureor otherwise determine an ambient air temperature sensor value 220. Theambient air temperature sensor value 220 is provided to the vehiclecontrol system 280 and may subsequently be used as a reference for bothof the models to determine a state of the air diverter valve 225.

When either outside air 205 or underhood air 210 is pulled into the airinduction system 200, the air passes through an air filter 230. Prior tothe air entering a compressor 245, the pre-compressor model generates anestimated ambient air temperature value. In this example, the estimatedambient air temperature value is represented as pre-compressor sensorvalue 240. The pre-compressor sensor value 240 is generated by apre-compressor sensor 235. In some examples, the pre-compressor sensorvalue 240 may be adjusted to compensate for a determined fan speed of anintercooler 260, a determined engine load and/or a determined speed ofthe vehicle.

The pre-compressor model compares the pre-compressor sensor value 240 tothe ambient air temperature sensor value 220 to determine two differentoutputs or values for two different variables. The first variable,referred to herein as a “pre-comp cold exceed” variable, is set to“true” when the ambient air temperature sensor value 220 is colder(e.g., has a lower temperature value) than the pre-compressor sensorvalue 240 for a threshold amount of time (e.g., two-hundred seconds).Otherwise, the pre-comp cold exceed variable may be set to “false.” Insome examples, the temperature difference between the pre-compressorsensor value 240 and the ambient air temperature sensor value 220 mustbe above a temperature difference threshold (e.g., fourteen degreesCelsius) for the threshold amount of time in order for the pre-comp coldexceed variable to be set to true.

For example, the pre-comp cold exceed variable may be set to true basedon an integral of positive values of a difference between thepre-compressor sensor value 240 and the ambient air temperature sensorvalue 220 integrated over a time period (e.g., two-hundred seconds). Adetermination of the integral may be based on the following equation:

Integral: Positive values of (the pre-compressor sensor value 240−theambient air temperature sensor value 220) integrated over two-hundredseconds.

Once the integral is determined, a value (e.g., true or false) of thepre-comp cold exceed variable may be determined as follows:

Pre-comp Cold Exceed: Integral>(200 seconds*14 Degrees Celsius).

The second variable, referred to herein as “pre-comp hot exceed”variable, is set to “true” when the ambient air temperature sensor value220 is warmer (e.g., has a higher temperature value) than thepre-compressor sensor value 240 for a threshold amount of time (e.g.,two-hundred seconds). Otherwise, the pre-comp hot exceed variable may beset to “false.” In some examples, the temperature difference between theambient air temperature sensor value 220 and the pre-compressor sensorvalue 240 must be above a temperature difference threshold (e.g.,fourteen degrees Celsius) for a threshold amount of time (e.g.,two-hundred seconds) in order for the pre-comp hot exceed variable to betrue.

For example, the pre-comp hot exceed variable may be set to true basedon an integral of positive values of a difference between thepre-compressor sensor value 240 and the ambient air temperature sensorvalue 220 integrated over a time period (e.g., two-hundred seconds). Adetermination of the integral may be based on the following equation:

Integral: Positive values of (the ambient air temperature sensor value220−the pre-compressor sensor value 240) integrated over two-hundredseconds.

Once the integral is determined, a value (e.g., true or false) ofpre-comp hot exceed variable may be determined as follows:

Pre-comp Hot Exceed: Integral>(200 seconds*14 Degrees Celsius).

Once the values for the pre-comp cold exceed variable and the pre-comphot exceed variable are determined, those values are temporarily stored(e.g., by the vehicle control system 280) until a value for a variableassociated with the intercooler efficiency model (referred to herein as“intercooler exceed” variable) is determined.

Although the example above indicates that values for the pre-comp coldexceed variable and the pre-comp hot exceed variable are determinedbefore the intercooler exceed variable, the present application is notso limited. In some examples, values for the pre-comp cold exceedvariable, the pre-comp hot exceed variable and the intercooler exceedvariable may be determined simultaneously or substantiallysimultaneously. In another example, a value for the intercooler exceedvariable may be determined prior to the values for the pre-comp coldexceed variable and/or the pre-comp hot exceed variable. In either case,all values for the pre-comp cold exceed variable, the pre-comp hotexceed variable and the intercooler exceed variable may need to bedetermined and subsequently analyzed to accurately determine a state ofthe air diverter valve 225.

The intercooler efficiency model may determine an estimated ambient airtemperature (T_(ambient_est)) using the same formula described abovewith respect to FIG. 1 . For example, the intercooler efficiency modelcalculates the Cooling Capacity of the intercooler 260 and determinesthe Ambient Flow and the Cooling Flow. These values are used todetermine the estimated ambient air temperature (T_(ambient_est)) suchas previously described. For convenience, this equation is reproducedbelow:

$T_{ambient\_ est} = \frac{\frac{1000P_{a}}{{kP}_{a}} \times p_{ambient} \times {Cooling}{Flow}}{R_{spec} \times p_{0} \times {Ambient}{Flow}}$

where R_(spec) is the specific gas constant of air and p₀ is thestandard density of air.

Once the estimated ambient air temperature (T_(ambient_est)) isdetermined, an output value (e.g., either true or false) for theintercooler exceed variable may be provided by the intercoolerefficiency model. For example, intercooler exceed variable may be set totrue based on an integral of positive values of a difference between theestimated ambient air temperature (T_(ambient_est)) and the ambient airtemperature sensor value 220 integrated over a time period (e.g.,two-hundred seconds). A determination of the integral may be based onthe following equation:

Integral: Absolute value of (T_(ambient_est)−the ambient air temperaturesensor value 220) integrated over two-hundred seconds.

Once the integral is determined, the value (e.g., true or false) of theintercooler exceed variable may be determined as follows:

Intercooler Exceed: Integral>(200 seconds*14 Degrees Celsius).

In some examples, the pre-compressor sensor 235 is more sensitive tochanges in the temperature of the air caused by a position of the airdiverter valve 225 when compared to the intercooler efficiency model.Thus, when the two models are used together to determine a state of theair diverter valve 225 and the likelihood of a true failure of theambient air temperature sensor 215, the resulting determination will bemore accurate when compared to each model being used alone.

In order to determine the state of the air diverter valve 225, thevalues for the pre-comp cold exceed variable, the pre-comp hot exceedvariable and the intercooler exceed variable may be compared against atruth table (shown in FIG. 7 ) to determine whether the air divertervalve 225 is in an inactive state (such as shown in FIG. 2A) or is in anactive state (such as shown in FIG. 2B).

FIG. 7 illustrates an example truth table 700 that may be used todetermine a state of an air diverter valve of a vehicle according to anexample. In the example shown in FIG. 7 , the boxes highlighted in grayrepresent conditions in which normal or expected operating behavior ofthe various sensors are represented. If other states in the truth table700 are found based on values for the pre-comp cold exceed variable, thepre-comp hot exceed variable, and the intercooler exceed variable, anindication may be triggered that one or more sensors of the airinduction system may be faulty and/or the state of the air divertervalve is indeterminable.

As shown in FIG. 7 , when the values of the intercooler exceed variable,the pre-comp cold exceed variable and the pre-comp hot exceed variableare false, it may be determined that an ambient air temperature sensor(e.g., ambient air temperature sensor 215 (FIG. 2A)) is functioningcorrectly. It may also be determined that an air diverter valve (e.g.,air diverter valve 225 (FIG. 2A)) is in an inactive state. As such,outside air is being pulled into an air induction system of the vehicle.

However, when the values of the intercooler exceed variable and thepre-comp hot exceed variable are false, and the value for the pre-compcold exceed variable is true, it may be determined that the ambient airtemperature sensor (e.g., ambient air temperature sensor 215 (FIG. 2A))is functioning correctly, but the air diverter valve (e.g., air divertervalve 225 (FIG. 2A)) is in an active state. As such, relatively warmerunderhood air is being pulled into an air induction system of thevehicle. In such cases, the vehicle control system may determine thatone or more diagnostics of the vehicle may need to be deactivated and/orthresholds for the one or more diagnostics may need to be adjusted.

FIG. 3 illustrates an example vehicle control system 300 of a vehicleaccording to an example. The vehicle control system 300 may communicateor otherwise be associated with an air induction system such as, forexample, air induction system 100 (FIG. 1 ). As such, the vehiclecontrol system 300 may be used to process various sensor values providedthe various sensors of the air induction system. The vehicle controlsystem 300 may also store information relating to various operatingconditions of the vehicle, a state of an air diverter valve,outputs/values of the various models described herein and so on.

The vehicle control system 300 may include a data collection system 310.The data collection system 310 may receive information from varioussystems, sensors, and components of the vehicle. In some examples, thedata collection system 310 may receive ambient air temperature sensorvalues from an ambient air temperature sensor. The data collectionsystem 310 may also receive a pre-compressor sensor value from apre-compressor sensor. In another example, the data collection system310 may receive intercooler inlet air temperature values from anintercooler inlet air temperature sensor and/or may receive intercooleroutlet air temperature values from an intercooler outlet air temperaturesensor.

The data collection system 310 may also receive vehicle operatingconditions, such as those shown and described with respect to FIG. 4 ,from a vehicle operating condition monitoring system 350. The datacollection system 310 may also communicate or otherwise work inconjunction with the pre-compressor model system 330 and/or theintercooler model system 340 to determine an estimated ambient airtemperature (T_(ambient_est)), the determined Ambient Flow thedetermined Cooling Flow, a value for the pre-comp cold exceed variable,a value for the pre-comp hot exceed variable and a value for theintercooler exceed variable. As this information is received, theinformation may be stored in a data storage system 320.

FIG. 5 illustrates a method 500 for determining whether to trigger anerror notification for a vehicle based on a comparison between anambient air temperature reading and an estimated ambient air temperatureaccording to an example. The method 500 may be performed by a vehiclecontrol system, such as, for example, vehicle control system 300 (FIG. 3), associated with a vehicle. In some examples, the vehicle controlsystem may be communicatively coupled with various sensors and systemsof an air induction system such as, for example, air induction system100 (FIG. 1 ).

In some examples, method 500 does not begin until a set of vehicleoperating conditions (e.g., vehicle operating conditions 400 (FIG. 4 ))are satisfied. If it is determined the set of vehicle operatingconditions are satisfied, the method 500 may begin.

Method 500 begins at operation 510 in which an ambient air temperaturesensor reading and/or a pre-compressor sensor reading are received. Theambient air temperature sensor reading may be received from an ambientair temperature sensor associated with the vehicle. The pre-compressorsensor reading may be received from a pre-compressor sensor associatedwith the vehicle.

The ambient air temperature sensor may be positioned outside of anengine compartment of the vehicle while the pre-compressor sensor may bepositioned within the engine compartment of the vehicle. In someexamples, the ambient air temperature sensor is positioned in sidemirror of the vehicle. Although specific locations are given, theambient air temperature sensor and the pre-compressor sensor may beprovided on any suitable location of the vehicle.

In operation 520, a Cooling Capacity of an intercooler of the vehicle isdetermined. As explained above, the Cooling Capacity of the intercoolermay be determined based on a determined air mass flow (Air_Mass_Flow)(e.g., the rate of fresh air flow through the air induction system), thespecific heat of air (CP), a temperature difference of air between anintercooler inlet air temperature sensor (T_(IC_in)) and an intercooleroutlet air temperature sensor T_(IC_out)), and a difference between thevalue (T_(IC_in)) provided by the intercooler inlet air temperaturesensor an estimated value for the ambient air temperature(T_(ambient_est)). As described with respect to FIG. 1 , the followingequation may be used to determine the Cooling Capacity of theintercooler:

${{Cooling}{Capacity}} = {\frac{{Air\_ Mass}{\_ Flow}}{1000g/{kg}} \times {CP} \times \frac{T_{IC\_ in} - T_{IC\_ out}}{T_{IC\_ in} - T_{ambient\_ est}}}$

Once the Cooling Capacity of the intercooler has been determined, flowproceeds to operation 530 and an Ambient Flow rate of the intercooler isdetermined. The Ambient Flow rate of the intercooler describes theability of the intercooler to cool air mass flow. In some examples, theAmbient Flow is adjusted based on a detected or determined ambientdensity of air.

The Ambient Flow rate is based, at least in part, on the determined airmass flow and the Cooling Capacity of the intercooler. In some examples,values for the air mass flow and the Cooling Capacity are stored in adata table, a lookup table, a tunable map or other such storage device.Thus, when the air mass flow and the Cooling Capacity is determined,these values may be used to determine a pre-calculated/calibratedAmbient Flow rate. In some examples, ambient density of air is accountedfor when determining the Ambient Flow rate.

Flow then proceeds to operation 540 and a Cooling Flow rate of theintercooler is determined. The Cooling Flow rate of the intercooler isbased, at least in part, on a function of the fan speed of theintercooler and the speed of the vehicle. In some examples, values forthe fan speed of the intercooler and the speed of the vehicle are storedin a data table, a lookup table, a tunable map or other such storagedevice. Thus, when those values are received, the Cooling Flow rate ofthe intercooler may be determined. In some examples, the Cooling Flow isnot adjusted or otherwise does not account for ambient density of air.

In operation 550 an estimated ambient air temperature (T_(ambient_est))is determined. The estimated ambient air temperature (T_(ambient_est))may be based on the amount of heat rejected by the intercooler. Theestimated ambient air temperature (T_(ambient_est)) is determined usingthe pre-compressor sensor value (p_(ambient)) provided by thepre-compressor sensor, the determined Cooling Flow rate, and thedetermined Ambient Flow rate. The following equation may be used todetermine estimated ambient air temperature (T_(ambient_est)):

$T_{ambient\_ est} = \frac{\frac{1000P_{a}}{{kP}_{a}} \times p_{ambient} \times {Cooling}{Flow}}{R_{spec} \times p_{0} \times {Ambient}{Flow}}$

where R_(spec) is the specific gas constant of air and p₀ is thestandard density of air.

Flow then proceeds to operation 560 and a difference (represented asT_(error)) between the estimated ambient air temperature(T_(ambient_est)) and the ambient air temperature sensor value(T_(ambient_sensor)) is determined. The difference between these valuesis determined using the following equation:

T _(error) =|T _(ambient_sensor) −T _(ambient_est)|

In operation 570 a determination is made as to whether the differencebetween the estimated ambient air temperature (T_(ambient_est)) and theambient air temperature sensor value (T_(ambient_sensor)) is above adetermined temperature difference threshold for a determined period oftime. In some examples, the temperature difference threshold is fourteendegrees Celsius (although other values may be used) and the determinedperiod of time is two-hundred seconds (although other periods of timemay be used).

If the determined difference between the estimated ambient airtemperature (T_(ambient_est)) and the ambient air temperature sensorvalue (T_(ambient_sensor)) is not above the determined temperaturedifference threshold for the determined period of time, flow proceedsback to operation 510 and the method 500 may repeat.

However, if the determined difference between the estimated ambient airtemperature (T_(ambient_est)) and the ambient air temperature sensorvalue (T_(ambient_sensor)) is above the determined temperaturedifference threshold for the determined period of time, flow proceeds tooperation 580 and the vehicle control system causes an errornotification to be triggered. Triggering an error notification may causea check engine light or a malfunction indicator light of the vehicle tobe illuminated or other error message to be displayed. The indicationmay communicate that the ambient air temperature sensor is faulty.

FIG. 6 illustrates a method 600 for determining a state of an airdiverter valve of a vehicle according to an example. The method 600 maybe performed by a vehicle control system, such as, for example, thevehicle control system 300 (FIG. 3 ), as the vehicle control systemreceives information from various sensors of an air induction system,such as, for example, air induction system 100 (FIG. 1 ). In someexamples, method 500 (FIG. 5 ) (or various operations of method 500) maybe executed in simultaneously or substantially simultaneously with thevarious operations described with respect to method 600.

In some aspects, some of the operations described with respect to FIG. 6may not proceed until some of the operations described with respect toFIG. 6 have been completed. For example, some of the operations inmethod 600 may not proceed until operations 620, 630, 650, and/or 660have been completed. Thus, one or more operations of method 600 mayeffectively be put on hold until a first ambient temperature estimateand a second ambient temperature estimate are determined and/or valuesfor a pre-comp cold exceed variable, a pre-comp hot exceed variableand/or an intercooler exceed variable are determined.

Method 600 begins at operation 610 in which an ambient air temperaturereading and/or a pre-compressor sensor reading are received. The ambientair temperature reading may be received from an ambient air temperaturesensor associated with the vehicle. The pre-compressor sensor value maybe received by a pre-compressor sensor associated with the vehicle suchas previously described.

Flow then proceeds to operation 620 in which a first ambient airtemperature estimate is determined. In some examples, the first ambientair temperature estimate is based on a first temperature model. Thefirst temperature model is referred to herein as the pre-compressormodel such as previously described.

The pre-compressor model generates an estimated ambient air temperatureusing the pre-compressor sensor reading provided by the pre-compressorsensor. In some examples, the pre-compressor sensor value is adjusted tocompensate for a determined fan speed of the intercooler, a determinedengine load and/or a speed of the vehicle.

Once the pre-compressor ambient air temperature estimate is determined,flow may proceed to operation 630 and a second ambient air temperatureestimate is determined. The second ambient air temperature (e.g., theestimated ambient air temperature (T_(ambient_est))) may be determinedusing the intercooler efficiency model described above.

Flow then proceeds to operation 640 and the first ambient temperatureestimate is compared with the ambient air temperature reading todetermine values for three different variables. These variables arereferred to herein as the intercooler exceed variable, the pre-comp coldexceed variable and the pre-comp hot exceed variable.

The estimated ambient air temperature is used to determine an outputvalue for the intercooler exceed variable. The value may be either trueor false based, at least in part, on the output of the intercoolerefficiency model such as described above.

The pre-comp cold exceed variable is set to true when the ambient airtemperature sensor value has a lower temperature value than thepre-compressor sensor value for a threshold amount of time. Otherwise,the pre-comp cold exceed variable may be set to false. As previouslyexplained, the temperature difference between the pre-compressor sensorvalue and the ambient air temperature sensor value may be required to beabove a temperature difference threshold (e.g., fourteen degreesCelsius) for the threshold amount of time in order for the pre-comp coldexceed variable to be set to true.

The pre-comp hot exceed variable is set to true when the ambient airtemperature sensor value has a higher temperature value than thepre-compressor sensor value for a threshold amount of time. Otherwise,the pre-comp hot exceed variable may be set to false. As previouslyexplained, the temperature difference between the ambient airtemperature sensor value and the pre-compressor sensor value may berequired to be above a temperature difference threshold (e.g., fourteendegrees Celsius) for the threshold amount of time in order for thepre-comp hot exceed variable to be set to true.

In operation 650, the values for the pre-comp cold exceed variable, thepre-comp hot exceed variable and the intercooler exceed variable areused to determine a state of the air diverter valve. In some examples,the values for the pre-comp cold exceed variable, the pre-comp hotexceed variable and the intercooler exceed variable may be comparedagainst a truth table (e.g., output states 700 (FIG. 7 )) to determine(operation 670) whether the air diverter valve is in an inactive stateor is in an active state.

For example, if the intercooler exceed variable, the pre-comp coldexceed variable and the pre-comp hot exceed variable are all false, theengine control system may determine that an air diverter valve of an airinduction system is in an inactive state. As such, outside air is beingpulled into an air induction system of the vehicle. The engine controlsystem may also determine that an ambient air temperature sensorassociated with the vehicle is functioning correctly.

When the intercooler exceed variable and the pre-comp hot exceedvariable are set to false and the pre-comp cold exceed variable is setto true, the vehicle control system may determine that the ambient airtemperature sensor that the air diverter valve is in an active state. Assuch, underhood air is being pulled into an air induction system of thevehicle. The engine control system may also determine that the ambientair temperature sensor of the vehicle is functioning correctly

In operation 660, one or more operations may be performed based on thedetermined state of the air diverter valve. For example, if the vehiclecontrol system determines that the air diverter valve is in an activestate, thresholds for one or more diagnostics may be changed. In otherexamples, one or more diagnostics may be deactivated until the airdiverter valve is in an inactive state. In another example, the vehiclecontrol system may determine that an error notification should betriggered based on the ambient temperature sensor reading and adetermined state of the air diverter valve.

FIG. 8 is a system diagram of a computing device 800 according to anexample. The computing device 800, or various components and systems ofthe computing device 800, may be integrated or associated with thevarious systems and/or subsystems described herein. For example, vehiclecontrol system 175 or 280 may be implemented in or using the computingdevice 800. As shown in FIG. 8 , the physical components (e.g.,hardware) of the computing device are illustrated and these physicalcomponents may be used to practice the various aspects of the presentdisclosure.

The computing device 800 may include at least one processing unit 810and a system memory 820. The system memory 820 may include, but is notlimited to, volatile storage (e.g., random access memory), non-volatilestorage (e.g., read-only memory), flash memory, or any combination ofsuch memories. The system memory 820 may also include an operatingsystem 830 that controls the operation of the computing device 800 andone or more program modules 840. The program modules 840 may beresponsible for receiving input, processing information, storinginformation, triggering error notifications and so on. Additionally oralternatively, the vehicle control system 850 may be responsible forreceiving input, processing information, triggering error notificationsand so on. The memory 820 may also store and/or provide similarinformation and details. While executing on the processing unit 810, theprogram modules 840 may perform the various processes described above.

The computing device 800 may also have additional features orfunctionality. For example, the computing device 800 may includeadditional data storage devices (e.g., removable and/or non-removablestorage devices) such as, for example, magnetic disks, optical disks, ortape. These additional storage devices are labeled as a removablestorage 860 and a non-removable storage 870.

Examples of the disclosure may also be practiced in an electricalcircuit comprising discrete electronic elements, packaged or integratedelectronic chips containing logic gates, a circuit utilizing amicroprocessor, or on a single chip containing electronic elements ormicroprocessors. For example, examples of the disclosure may bepracticed via a system-on-a-chip (SOC) where each or many of thecomponents illustrated in FIG. 8 may be integrated onto a singleintegrated circuit. Such a SOC device may include one or more processingunits, graphics units, communications units, system virtualization unitsand various application functionality all of which are integrated (or“burned”) onto the chip substrate as a single integrated circuit.

When operating via a SOC, the functionality, described herein, may beoperated via application-specific logic integrated with other componentsof the computing device 800 on the single integrated circuit (chip). Thedisclosure may also be practiced using other technologies capable ofperforming logical operations such as, for example, AND, OR, and NOT,including but not limited to mechanical, optical, fluidic, and quantumtechnologies.

The computing device 800 may include one or more communication systems880 that enable the computing device 800 to communicate with othercomputing devices 895. Examples of communication systems 880 include,but are not limited to, wireless communications, wired communications,cellular communications, radio frequency (RF) transmitter, receiver,and/or transceiver circuitry, a Controller Area Network (CAN) bus, auniversal serial bus (USB), parallel, serial ports, etc.

The computing device 800 may also have one or more input devices and/orone or more output devices shown as input/output devices 885. Theseinput/output devices 885 may include a keyboard, a sound or voice inputdevice, haptic devices, a touch, force and/or swipe input device, adisplay, speakers, etc. The aforementioned devices are examples andothers may be used. The computing device 800 may also include varioussensors 890 such as described herein.

The term computer-readable media as used herein may include computerstorage media. Computer storage media may include volatile andnonvolatile, removable and non-removable media implemented in any methodor technology for storage of information, such as computer readableinstructions, data structures, or program modules.

The system memory 820, the removable storage 860, and the non-removablestorage 870 are all computer storage media examples (e.g., memorystorage). Computer storage media may include RAM, ROM, electricallyerasable read-only memory (EEPROM), flash memory or other memorytechnology, CD-ROM, digital versatile disks (DVD) or other opticalstorage, magnetic cassettes, magnetic tape, magnetic disk storage orother magnetic storage devices, or any other article of manufacturewhich can be used to store information and which can be accessed by thecomputing device 800. Any such computer storage media may be part of thecomputing device 800. Computer storage media does not include a carrierwave or other propagated or modulated data signal.

Communication media may be embodied by computer readable instructions,data structures, program modules, or other data in a modulated datasignal, such as a carrier wave or other transport mechanism, andincludes any information delivery media. The term “modulated datasignal” may describe a signal that has one or more characteristics setor changed in such a manner as to encode information in the signal. Byway of example, and not limitation, communication media may includewired media such as a wired network or direct-wired connection, andwireless media such as acoustic, radio frequency (RF), infrared, andother wireless media.

The description and illustration of one or more aspects provided in thisapplication are not intended to limit or restrict the scope of thedisclosure as claimed in any way. The aspects, examples, and detailsprovided in this application are considered sufficient to conveypossession and enable others to make and use the best mode of claimeddisclosure. The claimed disclosure should not be construed as beinglimited to any aspect, example, or detail provided in this application.Regardless of whether shown and described in combination or separately,the various features (both structural and methodological) are intendedto be selectively rearranged, included or omitted to produce anembodiment with a particular set of features. Having been provided withthe description and illustration of the present application, one skilledin the art may envision variations, modifications, and alternate aspectsfalling within the spirit of the broader aspects of the generalinventive concept embodied in this application that do not depart fromthe broader scope of the claimed disclosure.

What is claimed is:
 1. A system, comprising: a processor; and a memorycommunicatively coupled to the processor and storing instructions that,when executed by the processor, perform operations, comprising:receiving an ambient air temperature reading from an ambient airtemperature sensor associated with a vehicle; determining a coolingcapacity, ambient air flow rate and cooling flow rate associated with anintercooler of the vehicle; determining an estimated ambient airtemperature based, at least in part, on the cooling capacity, theambient air flow rate and the cooling flow rate; determining adifference between the ambient air temperature reading and the estimatedambient air temperature; and based on the determined difference betweenthe ambient air temperature reading and the estimated ambient airtemperature, eliminate an inaccurate fail notification caused by theambient air temperature sensor.
 2. The system of claim 1, wherein theambient air flow rate through the intercooler is based, at least inpart, on a rate of air flow through an engine induction system of thevehicle and the cooling capacity of the intercooler.
 3. The system ofclaim 1, wherein determining the ambient air flow rate through theintercooler comprises instructions for looking up the ambient air flowrate through the intercooler in an ambient air flow rate lookup table.4. The system of claim 1, wherein the cooling flow rate of theintercooler is based, at least in part, on an intercooler fan speed ofthe vehicle and a current speed of the vehicle.
 5. The system of claim1, wherein determining the cooling flow rate of the intercoolercomprises instructions for looking up the cooling flow rate of theintercooler in a cooling flow rate lookup table.
 6. The system of claim1, further comprising instructions for triggering an error notificationfor the vehicle when the determined difference between the ambient airtemperature reading and the estimated ambient air temperature is over athreshold for a predetermined amount of time.
 7. The system of claim 1,further comprising instructions for determining the ambient air flowrate through the intercooler associated with the vehicle when a set ofoperating conditions of the vehicle are satisfied.
 8. The system ofclaim 7, wherein the set of operating conditions comprise two or moreof: a speed of an engine of the vehicle exceeding an engine speedthreshold for over a predetermined amount of time; the ambient air flowrate through the intercooler exceeding an ambient air flow rate minimumvalue; a temperature of a coolant associated with the vehicle exceedinga coolant temperature minimum value; a run time of the engine of thevehicle exceeding an engine run time minimum value; a determined ambientair pressure exceeding an ambient air pressure minimum value; a currentspeed of the vehicle exceeding a minimum vehicle speed threshold; adetermination as to whether the vehicle is idling; a determined crankpower of a crankshaft associated with vehicle exceeding a crank powerminimum threshold; a determined output power of the engine being withinan output power range; a time frame associated with the estimatedambient air temperature exceeding a minimum estimated ambient airtemperature time frame value; or a determined fan speed of a cooling fanassociated with vehicle is within a cooling fan speed range.
 9. Amethod, comprising: receiving an ambient air temperature reading from anambient air temperature sensor associated with a vehicle; determining anestimated ambient air temperature based, at least in part, on a coolingcapacity, an ambient air flow rate and a cooling flow rate associatedwith an intercooler of the vehicle; determining a difference between theambient air temperature reading and the estimated ambient airtemperature; and based on the determined difference between the ambientair temperature reading and the estimated ambient air temperature,eliminating an inaccurate fail notification caused by the ambient airtemperature sensor.
 10. The method of claim 9, wherein the threshold isfourteen degrees Celsius.
 11. The method of claim 9, further comprisingtriggering an error notification for the vehicle when the determineddifference between the ambient air temperature reading and the estimatedambient air temperature is above a threshold for a predetermined amountof time.
 12. The method of claim 11, wherein the predetermined amount oftime is two-hundred seconds.
 13. The method of claim 9, wherein theambient air temperature sensor is outside of an engine compartment ofthe vehicle.
 14. The method of claim 9, wherein the ambient air flowrate through the intercooler is based, at least in part, on a rate ofair flow through an engine induction system of the vehicle and thecooling capacity of the intercooler.
 15. The method of claim 9, whereinthe cooling flow rate of the intercooler is based, at least in part, onan intercooler fan speed of the vehicle and a current speed of thevehicle.
 16. The method of claim 9, further comprising determining theambient air flow rate through the intercooler associated with thevehicle when a set of operating conditions of the vehicle are satisfied.17. The method of claim 16, wherein the set of operating conditionscomprise two or more of: a speed of an engine of the vehicle exceedingan engine speed threshold for over a predetermined amount of time; theambient air flow rate through the intercooler exceeding an ambient airflow rate minimum value; a temperature of a coolant associated with thevehicle exceeding a coolant temperature minimum value; a run time of theengine of the vehicle exceeding an engine run time minimum value; adetermined ambient air pressure exceeding an ambient air pressureminimum value; a current speed of the vehicle exceeding a minimumvehicle speed threshold; a determination as to whether the vehicle isidling; a determined crank power of a crankshaft associated with vehicleexceeding a crank power minimum threshold; a determined output power ofthe engine being within an output power range; a time frame associatedwith the estimated ambient air temperature exceeding a minimum estimatedambient air temperature time frame value; or a determined fan speed of acooling fan associated with vehicle is within a cooling fan speed range.18. A method, comprising: determining whether a set of vehicle operatingconditions are satisfied; and when the set of vehicle operatingconditions are satisfied: receiving an ambient air temperature readingfrom an ambient air temperature sensor associated with a vehicle;determining an estimated ambient air temperature based, at least inpart, on a cooling capacity, an ambient air flow rate and a cooling flowrate associated with an intercooler of the vehicle; determining adifference between the ambient air temperature reading and the estimatedambient air temperature; and based on the determined difference betweenthe ambient air temperature reading and the estimated ambient airtemperature, eliminating an inaccurate fail notification caused by theambient air temperature sensor.
 19. The method of claim 18, wherein theset of operating conditions of the vehicle are selected from a groupcomprising: a speed of an engine of the vehicle exceeding an enginespeed threshold for over a predetermined amount of time; the ambient airflow rate through the intercooler exceeding an ambient air flow rateminimum value; a temperature of a coolant associated with the vehicleexceeding a coolant temperature minimum value; a run time of the engineof the vehicle exceeding an engine run time minimum value; a determinedambient air pressure exceeding an ambient air pressure minimum value; acurrent speed of the vehicle exceeding a minimum vehicle speedthreshold; a determination as to whether the vehicle is idling; adetermined crank power of a crankshaft associated with vehicle exceedinga crank power minimum threshold; a determined output power of the enginebeing within an output power range; a time frame associated with theestimated ambient air temperature exceeding a minimum estimated ambientair temperature time frame value; or a determined fan speed of a coolingfan associated with vehicle is within a cooling fan speed range.
 20. Themethod of claim 18, further comprising triggering an error notificationfor the vehicle when the determined difference between the ambient airtemperature reading and the estimated ambient air temperature is above athreshold for a predetermined amount of time.